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September 23 2015

when faster random is needed, take this!

openssl enc -aes-256-ctr -pass pass:"$(dd if=/dev/urandom bs=128 count=1 2>/dev/null | base64)" -nosalt < /dev/zero > randomfile.bin

.. suddenly the limit is not the CPU anymore, but the bus to the drive carrying the filesystem :)

and when one wants to see some numbers, add pv in between:

openssl enc -aes-256-ctr -pass pass:"$(dd if=/dev/urandom bs=128 count=1 2>/dev/null | base64)" -nosalt < /dev/zero | pv -pterb > /dev/sdb

November 26 2014

osx mavericks after yosemite release with a working recovery partition to acutally use FileVault - a story of pain!

the jungle of replacing a failing hard drive in a mac book pro and not wanting yosemite afterwards!

Why? well, after fsck'ing the machine without errors but still having an unbearable slow user experience - the spinning ball takes ~15 minutes until a click to the username in the login manager reacts and no chance to use the system after login, as well as even tab expension in single user mode takes ages - I finally decided that either the hdd is failing, a cable is faulty or the motherboard is dying. Or, before that to check, lets reinstall Mavericks to make sure it is not some strange config issue in the former installed OS.

Why not yosemite? well, default submission of spotlight search requests to Apple and Microsoft? Sure, one can disable that, but what else hidden anti-privacy "features" are there? I do not trust, yet. So Mavericks it shall be!

Uhm, where do I get the installer? Ah yes, Appstore. Wait, no, only if you previously downloaded it with the corresponding AppleID. Didn't. Bummer. So no Mavericks anymore for me?

Ok, Mavericks is free of charge so it might not be illegal to just download it somewhere else. Sure, I go and download a Mavericks image which I can put directly to an USB stick to install on the machine then.

Good. Install runs, takes ages. Actually never finishes m( Alrite, check! replacing hard drive is what we do now!

Open the thing up, easy: just some screws. Ok, the torx for the HDD screws is annoying, but no issue. Let's install that Mavericks again! Takes only 30-40 minutes and is done. Yeah \o/

No, I cannot activate FileVault? Research brings that I should not never ever use HFS Journalling with Capitals .. ok, redo the thing, another HFS. Another hour, done, fine.

F***. No FileVault again? Missing recovery maybe? Ok, lets get that "Recovery Partition Creator" which is recommended for that case. Run it. Ok, it takes ages, does not respond, is obviously doing nothing. Grrr .. Tried to run it in single user mode console, no chance. That thing seem broken for me.


Ok, once having installed Mavericks, the interwebbs suggests to just reinstall it from the downloaded Installer again - to get the recovery partition (re-)created. Over itself. Well, ok. Lets click that installer I have on the stick!

I see, it wants to connect to the AppStore to verify the machine with Apple .. wait whut? Ah, nevermind, lets just get over this!

On a fresh OSX you need an AppleID to use the AppStore. Ok, do it. Wait, needs credit card? Are you nuts? Why? Okok, after another hour researching I find a way to create an AppleID without the need of credit card credentials (by downloading a "free" app in the AppStore and creating an AppleID just from that dialog there, then one gets offered the "None" button for payment method ..) .. are you serious?!

Kewl, I am now in the AppStore after clicking my installer .. and .. yeah. "The product you are looking for is not available at the moment." Nice, I created 3 AppleIDs, wasted numerous email aliases to learn that I cannot install Mavericks, again?

Alrite. Maybe that installer I downloaded somewhere is faulty. I try to get an original one. That maybe should create the recovery partition upon install (remember: to get file vault running!!)! I ask around, look through all Macs I have around and - voila - I actually do find a already downloaded Mavericks Installer of ~6GB size.

I put that on the stick with: sudo /Applications/Install\ OS\ X\ \ --volume /Volumes/MyStick \ --applicationpath /Applications/Install\ OS\ X\ \ --nointeraction

Takes an hour, I can boot it. I install it. It says "8 minutes to go", not very long, uh? Reboots. Lands in the installer - again, says "50 minutes to go". Okaaaayyyyyyyyy .. at least it does something.

End of journey: it installed. The former created users are still there. So what did it actually do? Not a complete fresh install for sure. Nevermind. Lets see system preferences: activate FileVault .. aaaand ?!

it actually does it. reboots. tells me it needs another 6 hours until done with the ecryption! wow! only 2 days wasted! to re-install a Mavericks with a useable recovery partition to actually use file vault!

thanks for listening. dafuq!?

slightly related, did you dry these in the rain forest?!?:

September 04 2014

Install recent on any *debian

as root:

curl -sSL | sudo sh
usermod -aG docker youruser


do not depend on distribution packages .. ;_)

August 26 2014

add own ca to debian/ubuntu

to get your own CA (easily created with tinyca) into your debian/ubuntu system as an accepted CA do this:

actually it seems, the update-ca-certificates script accepts only files named .crt .. so place your .pem there named .crt .. :D

:# cp your-ca.crt /usr/local/share/ca-certificates
:# update-ca-certificates

voila, it is now imported :)

you can check what the above script actually did with:

:# ls -al /etc/ssl/certs/ | grep your-ca

August 20 2014

systemd on jessie (testing)

test driving systemd on jessie

recently, i saw updates to udev were failing on a jessie vm. the reason was that the vm was running on an older kernel that for other reasons could not be upgraded. as such, /dev did not contain a lot of entries which successfully prevented the vm from booting. manually mounting/chrooting its root file system in the dom0 let me uninstall systemd-* and get back to sysvinit-core. for lack of /dev entries i had to resort to installing makedev which got the box running again.

it was time to also dist-upgrade a laptop that had initially been installed with squeeze, back then running on different hardware. now this laptop has multiarch running, with A LOT of installed packages (roughly 5000). Many of the installed services were just installed for testing and disabled to start up by renaming their links in /etc/rc[1-5].d from uppercase S10_foobar to s10_foobar which kept on working when i dist-upgraded the box to wheezy.

after the dist-upgrade, i found ALL software installed to be running. not too much of a biggie, i set about to disable these services again using systemctl and got most of the stuff disabled. samba still refused to be turned off though. to be fair, some stuff that had been broken since the upgrade to wheezy suddenly started working again, ie plugging usb sticks in and being able to mount the via gui or slamming the lid of the laptop would actually make it suspend.

having stuff that was not supposed to be running is one thing. booting seemed to a bit quicker, but for not running a display manager i still had to wait until all of the virtual consoles came up. what put me off though was that i was suddenly experiencing shutdown times like i was running windows, shutdown took from anywhere about 30 seconds to several minutes. debugging was a bit difficult as the syslogd got stopped very early.

ok, this is probably very beta and as i am running testing, it probably is normal to encounter a few glitches. maybe it will get better some day.

ok again, how am i going to fix it ? let's revert to the old sysvinit.



sigh ok, fuck it, whatever.

deinstalling systemd means some of the gnome apps will have to be deleted. fortunately this box runs xfce. goodbye, aptdaemon brasero colord gconf-editor gnome-sushi gvfs gvfs-backends gvfs-daemons gvfs-fuse hplip libpam-systemd nautilus nautilus-sendto packagekit packagekit-tools policykit-1 policykit-1-gnome printer-driver-postscript-hp udisks2, hoping to be able to install you some day again.

oh, php5-fpm is gone too. maybe the project maintainers should not so aggressively try to impose their software onto users. now if i need a box that has to run php-fpm i am forced to having systemd on it ? this is getting ridiculous. The Depends- and Conflicts- fields seem deliberately fucked to give people no other choice than systemd.

ah, the resolution of the 2nd monitor is not kept anymore and i have to manually set it each time X is started. hm. last time i got it fixed by briefly installing a display manager. lets try gdm3 or lightdm or so.

doh. both rely on systemd and i can't have them running with sysvinit-core. WTF ? the universal operating system is denying choices ?

this sucks.

to summarize,

systemd needs a new kernel and the system will not work with an older one. it does a lot and as usual, the development is quicker than the documentation being written. it also acts as a service monitor.

this concept does not look like unix, it looks like redmond. it is not small and beautiful, but a huge chunk of functionality with a lot of different things it is supposed to do.

being so intrusive to make it mandatory if one wants to run ie gnome apps sucks bonkers.

this does not feel like adding an alternative, it feels more like having constraints stuffed down ones throat while deliberately removing alternative choices.

March 21 2014

dmraid mdadm gpt grub woooes .. some snippets

as I fight all day with gpt, parted, debian-installer, dmraid, partition types and mdadm, I just put some useful snippets here. AFTER all this use the debian-installer or which distro you ever use, as those installers tend to mess up here big time, resulting in non-booting sytems.

get rid of former fakeraid metadata on your drives:

dmraid -rE

create a useful layout on sda

mklabel gpt
mkpart non-fs 1 2     # leave some space before in case one day a slightly smaller drive needs to sit in the raid :)
mkpart boot 2 1000
mkpart system 1000 -1 # leave some space after in case one day a slightly smaller drive needs to sit in the raid ..
set 1 bios_grub on
set 2 raid on
set 3 raid on

copy the gpt partition table from on drive to another WATCH OUT: FROM /dev/sdX TO /dev/sdY .. do not mess this up ..

sgdisk -R=/dev/sdY /dev/sdX
sgdisk -G /dev/sdY # this randomizes the GUID on disk & partitions

March 19 2014

fakeraid not seen in debian installer .. The F*** !?!

sometimes one could go crazy, took me ages to figure, that's why it is here now: in case the installer doesn't see the freshly created fakeraid (e.g. on hp proliant microserver ..), put that to your installer bootloader line:


this can save a day ..

March 10 2014


setfacl -R -m group:groupname:rw /path/to/dir
find /path/to/dir -type d -exec setfacl -m group:groupname:rwx {} \;
find /path/to/dir -type d -exec setfacl -m default:groupname:rwx {} \;

April 14 2013

clone lvm via ssh

one just creates the targetlv in the same size as the srclv (8g in this case),
and when telling pv this size for the transfer it shows all the bells and
whistles it can .. even ETA :_)

dd if=/dev/srcvg/srclv | 
pv -p -e -t  -r -a -s 8G | 
ssh -i /home/user/.ssh/sshprivatekey -C -c arcfour -l root 172.x.y.z 'dd of=/dev/targetvg/targetlv'

February 28 2013

January 25 2013

resonant lowpass gate panel

After getting to build two resonant lowpass gates, a design from old don buchla put into a pcb done by thomas white, i decided to make my own euro front panels for it and share them.

the files are available at github

(c) 1904-2038 wotwot


January 17 2013

December 27 2012

December 20 2012

December 07 2012


88:88 - buried in america

hmmm, i think i like it
Reposted fromtollskoef tollskoef

November 08 2012

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Reposted frompterodactor3000 pterodactor3000
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Reposted frompterodactor3000 pterodactor3000
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